Kinetics and Mechanism of the Anilinolysis of O-Ethyl Phenyl Phosphonochloridothioate in Acetonitrile
作者:Md. Ehtesham Ul Hoque、Hai-Whang Lee
DOI:10.5012/bkcs.2012.33.8.2707
日期:2012.8.20
investigated in acetonitrile at . The deuterium kinetic isotope effects (DKIEs) invariably increase from a secondary inverse DKIE ( = 0.93) to a primary normal DKIE ( = 1.28) as the substituent of nucleophile (X) changes from electron-donating to electron-withdrawing. These can be rationalized by the gradual transition state (TS) variation from a backside to frontside attack. A concerted mechanism is proposed
在乙腈中动力学研究了 O-乙基苯基硫代膦酰氯与取代苯胺 () 和氘代苯胺 () 的亲核取代反应。随着亲核试剂 (X) 的取代基从给电子变为吸电子,氘动力学同位素效应 (DKIE) 总是从次级逆 DKIE (= 0.93) 增加到初级正态 DKIE (= 1.28)。这些可以通过从背面到正面攻击的逐渐过渡状态(TS)变化来合理化。提出了一种协调机制。三角双锥型 TS 被提议用于背面攻击,而氢键四中心型 TS 被提议用于正面攻击。